Can’t Decide.

I’ve recently found out I was pregnant by someone I’ve been dating on and off for almost 8 years now. The problem is he already has 2 other kids by 2 other women( 1 kid he rarely sees the other he’s never met) . He’s not working or in school right now. I’m 21 and I just feel like I’m not ready. I also don’t want to bring my kid into a unstable situation. At the same time I feel bad and I feel selfish that I don’t want to be a mom yet. Please don’t too be harsh....